


Summer exchange

by Bitterblue



Category: Orphan Black (TV)
Genre: F/F
Language: English
Status: Completed
Published: 2014-07-13
Updated: 2014-08-30
Packaged: 2018-02-08 15:52:50
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 4,901
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/1947087
Author URL: https://archiveofourown.org/users/Bitterblue/pseuds/Bitterblue
Summary: <blockquote class="userstuff">
              <p>It's been 10 years since Delphine was sent to Frankfurt, and nearly 10 since she quit working for DYAD. Now a professor at a university at home in France, she runs a summer program for exchange students to do biology intensives and learn French in an immersion setting. Those students need chaperones. Delphine is surprised by one of them. Complete, 3/3.</p>
            </blockquote>





	1. Chapter 1

**Author's Note:**

  * For [thosefarplaces](https://archiveofourown.org/users/thosefarplaces/gifts).



Little things make lies of her insistence that she doesn't think about it anymore—not that there is anyone to insist  _to_. When she left DYAD, it had been a clean break.

_"Cosima is dead." Rachel's voice was cool, her face impassive over the video conference. Delphine wept, then, open and ashamed and entirely unable to stop._

_"I will kill you," she promised. Rachel laughed; something about her left eye didn't sit quite correctly in her face. She realized with a start that it was white, glossy like glass._

_"Cosima thought she would, too. But she failed, and you will fail if you try, Dr. Cormier. I have orders to fire you, not have you assassinated. Please do not make me break those."_

_"Fire me?" Delphine was laughing amongst the sobs, unsure what she felt anymore. Did she feel anything anymore? "Have I not been a good enough pawn for you?"_

_"No." Rachel considered her with her mismatched, eerie eyes, and sighed. "You've been a disappointment. But that is no longer my concern. Your work with DYAD is being terminated. I'm sending across the documents detailing your continued confidentiality agreements. Against my better judgement, we will allow you to continue in immunology provided you maintain all nondisclosure about your projects with us. You will not contact any of the others, though I doubt they would want to hear from you now." Her mouth quirked into something that was nearly a smile, but infinitely colder. "There is a severance package being delivered to your bank. Goodbye, Dr. Cormier."_

This is what crosses her mind as Delphine waits for her coffee at the café on campus: an absurd loop of  _Cosima would have chosen something iced_  and  _But I don't think about Cosima_  and  _I am a liar. Once a liar, always a liar._ The cup is hot enough she should pause before drinking, but perhaps losing a few layers of the roof of her mouth is penance.

There is a steady breeze, enough to rustle trees and her hair and to take the edge off the heat. It is undoubtedly summer, if the deserted campus was not clear enough. She walks towards her office, nursing the still-too-hot coffee. Summer is easier, and harder. She never saw Cosima in summer.

But, of course, she doesn't think of Cosima anymore.

The sound of shouting catches at the edges of her attention as she reaches her office building and the sweet relief of air conditioning. Delphine turns and spots the group of young exchange students pouring out of vans on the other side of a green space, their laughter raucous and delighted.  _Hopefully they are quieter in classes_. She smiles a little, then steps inside.

 

She genuinely likes doing the summer exchange classes, which is probably why she is offered them year after year. The exchange had been the brain-child of some dean or administrator who probably liked the idea of a cash flow beyond grants into the department over the summer more than genuine learning, but Delphine had been enthusiastic from the beginning: a hand-picked group of enthusiastic young students studying every aspect of biology they can get their hands on in a series of intensive courses, while in a language immersion setting? She would have killed for such an opportunity. The kids are always bright, usually polite, and a delight to teach. They remind her of Cosima, when she lets them. A glint of silver in a nose, ill-advised dreadlocks, a toothy grin. It is easy to picture her among them, her drive for information voracious.

An updated enrollment list is on her desk when she finally makes it into her office, and Delphine glances at it briefly. Names are all well and good, but it's faces she'll remember when she meets them at the opening dinner tonight. She puts down the coffee to cool. There are lesson plans to tweak and finalize, equipment to double check before they need it, a dinner she should probably change clothes before attending—sweat-soaked shirts are, perhaps, not the right impression to give a pack of hormonal youths in a foreign country with only the barest number of chaperones. With a groan, she heads back out into the heat to go home and change, coffee and list of students forgotten on the desk.

 

The dinner is an informal affair held in one of the labs that would otherwise go entirely unused over the summer. There are two dozen students, three chaperones, two of her TAs, and Delphine; the uncertain chatter in hesitant French makes her smile as she moves around the room to meet each student personally. By the end of the six weeks, they will be as confident as each group before them has become. She likes being part of that confidence.

An almost-familiar laugh rings high and bright above the crowd.  _She sounds like Cosima_. It makes her heart ache. Without quite intending to, Delphine turns to find the source, and spots a dark-haired woman with a slight frame, facing away from her. Her hair is short, almost a bob, with an unpredictable, wild sort of wave and faint threads of silver.  _It is highly unlikely there is a clone, after all these years, here_. The woman is laughing again, and it does sound like Cosima—so, perhaps, like all of them? Laughing at a young woman, taller than herself, with an almost-familiar smile, like the melody to a song Delphine didn't know she had forgotten. She has not met this student yet.

Her feet have her moving before Delphine's mind catches up, and her eyes are reading the name tag on the girl's jacket. She slows.  _Kira._ _Impossible_. But the girl has seen her, and smiles, waving.

"I am so excited to be here," she says to Delphine, and the dark haired woman turns, the laugh falling from her face in surprise.

A part of Delphine's rational mind whispers about  _genetic identicals_  and  _she's dead_  and  _this is not Cosima_ , but the expression of incredulous disbelief on her face is too familiar to belong to anyone else. Surely no other person, clone or otherwise, could look at her with such a mix of confusion and fear and longing. Surely, Delphine would not want them to. She takes in the woman before her, changed and  _not dead not dead not dead. Alive_. Very much alive, the nose ring in place but the dreadlocks gone. New frames, but still spectacled. Wearier, a sort of quiet restlessness in her. The woman twists her fingers together, her eyes cataloguing every line in Delphine's face.

She could not begin to guess how long they stare at each other before Delphine remembers herself and looks away, cheeks pink, to smile at the student. "I hope you will have an enjoyable time. Kira, non?" She offers her hand. "I'm Dr. Cormier, I'll be your lecturer for most of the subjects." Kira takes it, her grip firm, and smiles, too—and  _oh_ , she looks like Sarah.

"This is my Aunt Cosima, she's one of the chaperones."

The confirmation sends her reeling all over again, dropping Kira's hand to reach out to Cosima. Cosima, who is not dead. Cosima, who is  _here_. Cosima takes her hand, squeezing lightly, but she fumbles her smile and her voice cracks as she says, "Hi. Um. Enchantée, I guess."

She doesn't say  _you're alive_ , nor  _Rachel said you were dead_ , nor  _I cannot believe I believed anything Rachel said to me concerning you_ , nor  _I'm sorry I left they threatened you and Kira and all the others_ , nor  _I love you, I still love you, I will always love you_ , nor  _do you still love me?_  She finds herself smiling, a tenuous thing. "Delphine. Enchantée."

These are going to be a very good six weeks.


	2. Chapter 2

**Notes for the Chapter:**

> I swear this is done now, no more begging from the rest of you.

She doesn't see her again for two days, long enough that a significant part of Delphine is sure it was all a fever dream brought on by the sweltering summer heat. Cosima,  _here_. Cosima,  _alive_. She's had this dream before—more often than she'd like to admit. Ten years is three and a half thousand sleeps, give or take, all of them marred by blood-stained lips.

But then she's there, slipping into the back of the classroom and filling a desk behind the students. None of the other chaperones have ever come into the classes; there are no rules against it, but it's still a pleasant surprise to see her there.  _It was real. She's real_. If Delphine is distracted by her presence, though, it does not come through in her classroom. She only has two weeks to get through half a semester's worth of genetics before they change topics. No time for distractions.

Cosima lingers at the back of the room as the kids leave for lunch after a three hour long lecture. She's all hesitant smiles and half-formed ideas spelled out in the spread of her fingers and the arch of her wrists, watching Delphine steadily as she pulls together her materials and packs them into her briefcase.

"Are you waiting for me?"

"I thought maybe we could have lunch. Or sex. Probably lunch. It's kind of hard to talk during sex, y'know? Mouth's busy. And I kind of think we have a lot to talk about." Her delivery is casual, as if this is a perfectly reasonable thing to say in an only recently vacated classroom. Delphine is  _red_. She opens her mouth to respond, then closes it again, uncertain  _how_  to answer. Cosima laughs. "Okay, definitely lunch." Delphine would do anything to keep her laughing; there is no undercurrent of illness staining her mouth or her voice, just delight.

 

Lunch turns out to be a table at a very busy café a little ways off campus, Cosima dismissing the presumption that she should, perhaps,  _chaperone_  the students who she is being trusted to look after with a wave of her hand. "They'll be fine," she promises as they sit at the almost too-small table, knees pressed together. In the heat, it should be unpleasantly sweaty; Delphine's sundress leaves her knees bare and she can feel her skin slick and stick against Cosima's own, revealed by her shorts. It should be. Delphine is glad of her touch too much to complain.

"So," Cosima drawls after Delphine has ordered for them both, "I was kind of under the impression you were no longer alive. And I'm really glad you are— _really_ , really glad, in fact." She hums, thinking, hands dancing. "Maybe ecstatic is a better word. Jubilant. Elated." She touches the back of Delphine's hand, her fingertips burning into her skin and firing sparks up her arm. "But, uh, what with the whole not-dead  _thing_ , I'm dying to know why you didn't contact me." She grins, apparently despite herself. "Except I'm not dying. Obvs. Just in case that wasn't clear." Her smile grows conspiratorial, and she leans close across the table. One of her elbows nearly knocks over a glass of water. "They grew me new lungs in a  _vat_."

Delphine laughs, partly because she thinks she's meant to and partly because Cosima is gleeful in a way she has not seen in a very long time. "You're a terrible liar," she chastises.

"Scout's honour!" she swears, holding up the fingers that had been searing into Delphine's nervous system in a salute.

"I didn't contact you because I thought  _you_  were dead, as well, and Rachel made it clear that trying to contact the others would potentially harm them. They  _never_  liked me—" she turns her hand and captures Cosima's from the air, stalling her objection with the slip of their fingers together, "they never liked me, Cosima, and if you were dead and contacting them might be dangerous for them...well. I am a coward. I'm sorry. I thought I was keeping my promise to you, staying away from them when I had nothing but hurt to offer."

"She told you I was dead." It isn't a question, and there is something dark in her eyes. "She knew we had been in contact after you were transferred from my case, presumably knew  _I_  knew you were being sent to Frankfurt. She said you died on the plane. And I knew  _that_  was a lie, but I didn't put it past her to have killed you. I may or may not have participated in the loss of her eye." Her shoulders lift in a shrug, but her fingers stay tightly tangled with Delphine's. "And other things. So when you didn't contact me, and your phone was shut off, I believed it. I almost gave up, right after you left. I was  _so_  tired and  _so_  ready. But I dreamed about you." She laughs, almost self-conscious, blushing a little. "I had this dream where you promised to never leave me, and it was so good it brought me back to life."

Delphine snorts, and Cosima swats at her shoulder with her free hand. "Hey, don't knock my moment of religious experience. You were an  _angel_ , I swear to god, and you kept me from dying. And then she said you were dead, but I had these embryonic stem cells to work with and she wasn't in charge any more. It was hard, but I didn't want to die after you'd used your angel miracle on me."

"My angel miracle." It's hard not to sound a little incredulous, though Delphine thinks she sounds more than half adoring, too.

"You are the  _worst_  sceptic," Cosima groans. It sounds an awful lot like  _I love you._

They are interrupted by the waitress bringing salads to their table. While it is patently obvious she has to release Cosima's hand for either of them to eat, Delphine is still wistful at its loss. She must fail to hide it in her expression, as Cosima looks up from her food and starts to laugh.

"You are  _still_  such a puppy," she says around a mouthful of greens, fork dancing patterns in the air. "So. What has Dr. Cormier been doing in the past decade? Besides being the world's hottest professor. Married, two-point-five kids, a dog, white picket fence?" She looks half expectant, as if waiting for Delphine to contradict her, and half resigned.

Delphine laughs, pressing her knees against Cosima's as she leans forward. "Cosima. I thought you were  _dead_." Cosima's expression shifts into something too close to hurt; it tugs at Delphine's heart. They have hurt each other enough for a lifetime already. She reaches under the table and presses her hand to Cosima's leg, just above their tangled knees and just below the hem of her shorts. "Non,  _non_ , mon amour, not like that. I just mean…" she sighs, and glances around the busy café as she tries to gather her thoughts. "I thought you were dead, so I threw myself into work. I got a job here, I've done a lot of research, I've taught. I've tried to pretend I didn't spend half of my days thinking about you. I put the idea of romance behind me. If you were dead, I didn't  _want_  anyone else." Her voice softens a little, and she squeezes Cosima's thigh with her fingertips before pulling back and sitting up straighter. "I told you: I wasn't supposed to fall for you. But I did."

Cosima's smile is slow. Disbelieving. Radiant.

"Do you have plans for tonight? Or this afternoon? Or right now?"

Taking a bite of her salad and trying not to choke on it while she laughs, Delphine shakes her head. "I have to teach this afternoon. And  _you_  should be supervising your students. But I don't have dinner plans."

The look in Cosima's eyes makes her heart flutter nervously. "Good," she says, voice quiet and pitched low. "You do now."

 

The part of Delphine that likes her job feels very bad about the first tutorial session that afternoon. The students are split into smaller classes and lab sessions are held based on her lecture during the morning. Cosima slips in behind Kira, who gives them both an exasperated look that Delphine is very sure she remembers on Sarah's face. It is not her best session teaching—significantly worse than the morning. Cosima is  _distracting_ , now that they've spoken again. Cosima would be distracting in a crowd of hundreds, but in a class of eight students she is downright troublesome.

Still, the look on her face as she sidles up to Delphine after the students are released for the evening is probably worth it, all glinting canines and sharp eyes. Kira lingers in the door before rolling her eyes with a huff and going to catch up with the other students. It makes Cosima laugh, soft and warm.

Cosima laughing makes Delphine kiss her.

She hadn't quite meant to do this so soon—or in a classroom. Kissing Cosima feels familiar, and true, and right, even if her hair is pleasantly strange as she slides her fingers through it to press against her scalp. Her glasses bump differently against Delphine's cheeks. Cosima is still laughing, murmuring  _yes_  against Delphine's mouth; she takes this invitation to slip her tongue past Cosima's lips.

For half a moment, Delphine panics and nearly pulls away.  _Is this a clone? Is this an elaborate trick? Why?_  And then it comes to her: Cosima no longer tastes faintly of blood because she is no longer dying. The idea of it makes her groan, press closer, the fingers that are not tangled in Cosima's hair splay across her lower back and tease at the hem of her shirt.

"Whoa," Cosima says against and into her mouth. "In the  _lab_? You used to tell me off for this." She slips into a bad French accent, "Co-si-ma, we cannot have the sex in  _the lab_ , what if someone walks in?"

Delphine ignores her teasing, smiling. Her face is starting to hurt from smiling. It's the best thing she's felt in years. "No. Not here. Come home with me."

Cosima's eyes search her face for a long moment before she breaks into a lazy grin. "I guess this clears up my questions about if you'd still be into me. I mean, ten years—promises and intense declarations of love aside—it's a long time to wait."

"You did."  _I think_.

"Yeah, but I'm a hopeless romantic." Delphine considers her options, and kisses her again.

 

Cosima makes her excuses to the other chaperones as Delphine ducks into her office to grab her bag and keys. They meet outside the building and Cosima immediately tangles their fingers together, her grip strong.

"I am in super trouble. But. You're worth it." She squeezes. Delphine swallows the questions she has about trouble and if this is a good idea, squeezes back, and begins to walk towards her apartment.

They are silent for the first block before Delphine catches Cosima stealing sidelong glances at her and starts to laugh. "What?"

"I just can't quite get over the part where you're here, and  _alive_ , and taking me to your apartment to have your way with me." She says it like it's nothing, or everything. Delphine can feel her heart begin to race.

"You think so? I might just be bringing you home for coffee. I still have questions to ask you."

"So ask. Because I'm planning on being naked in your apartment."

She considers for a moment before speaking. "You're chaperoning Kira, so you must still be in contact with Sarah. What are you doing now besides this? Did you...I have a right to know, if you're in a relationship."

"No relationship—I thought I cleared that up earlier. I wasn't joking. I waited. I mean, I wasn't  _waiting_  because you were dead, but I wasn't trying to find anyone. You kind of crushed me." Her voice is light, but Delphine can hear the old hurt under her cheerfulness. "And I teach high school biology now. You know the thing, those that can't, teach? I can't. DYAD sort of had me blackballed after I finished my PhD. So I teach."

There are dozens of questions she wants to ask, but they are at her building, so Delphine unlocks the door with a shy smile and holds it open for Cosima. The silence is anticipatory as Cosima leans against the wall, waiting for her to unlock the door to her apartment, too. It makes Delphine's smile broaden into a wicked sort of grin.

They are barely inside before Cosima's mouth is on hers again, kissing her with an intensity that sends heat pooling low in her hips. Delphine whimpers, trying to catch her breath, and slips both of her hands under Cosima's shirt, pushing it up her back slowly and spreading her fingertips against flushed skin. Cosima nips at her lower lip, tugging with her teeth slowly, then soothes with her tongue.

"You still taste the same," she groans as she encourages Delphine to tilt her head back and allow Cosima to taste her throat, her bites careful—at least one of them has the good sense not to leave incriminating marks that all of Delphine's students would surely see. Delphine groans again, arching against her.

"You don't," she pants, and the smile Cosima gives her could probably keep her heart feeling warm and happy for the rest of forever, no matter what comes next.

Cosima seems intent on  _nudity_  coming next, skating her hands up Delphine's back to find the fastening of her dress. She finds it with a smirk, tugging it down.

"Let me at least get you to bed," Delphine says, even as she moves to shrug off the dress and let it pool around her feet. Instead, still smirking, Cosima drops to her knees and places her hands on Delphine's hips, toying with the edge of her underwear. " _Merde_ , like this? You've gone impatient in your old age." She covers Cosima's hands with her own, and tugs the scrap of fabric down, stepping out of it and laughing self-consciously.

Fingers swirl in spirals across the plane of her hips, the tops of her thighs, the smooth dip of her belly. " _I'm_  impatient? You're the one mostly naked," Cosima points out helpfully before leaning in and helping Delphine settle one leg across her shoulder. She should feel exposed, open like this, with a woman who is practically a stranger after ten years apart settling in between her legs—a stranger, or a  _ghost_. She should, and does not; nothing has ever felt more like  _home_  than Cosima's breath across her inflamed skin, slick with want. Cosima seems to sense something of this, and waits.

"S'il te plaît." Her hips press forward only half voluntarily. The same searing smile from before dances in Cosima's eyes as her mouth comes down on Delphine. She should have forgotten how Delphine likes to be touched, surely, but there is no hesitancy in her mouth or her fingers. "Je t'aime, je t'aime," she swears between gasps and the press of fingers and tongue. She will swear this every moment to make up for ten years.

Delphine comes, and it feels like coming home.


	3. Chapter 3

The background bustle of the café has long since faded to the periphery of her attention, a not-quite pattern of chatter and china. All she can focus on is Cosima, here in front of her.

She has been all Delphine could focus on for nearly six weeks.

Part of her is distantly apologetic about the exchange education this year's students have received. Most of her is too busy thinking about six weeks of Cosima, alive and in her bed nearly every night—which, even on the nights they spent truly sleeping, has been blissful—or Cosima, returning to Canada in no time at all. She vacillates between the two: heady pleasure of the immediate past and aching pain of the immediate future. She  _knows_  she hasn't done as good a job this year as she has before, and it does sting to know she has let down these students—but every time she starts to mind, Cosima is there again and she is swept up in the moment.

" _Delphine_ , hey—" Cosima is grinning and laughing, waving her hands. Their finished lunch plates awaiting collection by a busboy lay scattered between them. "Where were you, Neptune? You were totally zoned out." Delphine finds the corners of her mouth are pulling into a smile she doesn't entirely feel; Cosima laughing makes the start of a laugh bubble deep in the hollow of her stomach as much as her smile creates its own echo across Delphine's face. Everything she is has become a reaction to the woman sitting here with their knees tangled together, so much that Delphine cannot remember what her existence was before Cosima. She should probably mind it, but instead she just feels that echo-smile tug at her mouth again.

"Pardonne, I was just…" she shrugs, and reaches over to touch the back of Cosima's hand, halting its arc through the unsatisfactory vent of the small air conditioner failing to keep the café at all cool in the early August heat. "I was thinking." It's meant to come off casually—they are in a crowded café (one that Delphine will forever think of as  _theirs_ )—but instead is nearly a drawl.

Every time she thinks she's become used to the predatory way Cosima's eyes light up at that tone, Delphine is surprised to find herself blushing and wanting to stumble away.

"Thinking, huh?" Smaller fingers twist under Delphine's hand until they tangle together, which somehow feels obscene in this bustling place. She is probably blushing now. Cosima laughs, just once, low and soft.  _Definitely_  blushing. "Well, I like ideas. And I like you. You usually have really good ideas, so...share."

It isn't a question, but she likes this game. "In  _public_ , non,  _Cosima_. No."

More laughter, warm in a way that is too much and nothing like the heat outside. "Well, now I  _really_  want to know. Something you won't tell me in public is automatically interesting."

"I will tell you later," she promises, and goes to pay.

 

Later turns out to be after one of the last labs (trying to fit in too much in too little time to make up for the first hazy few weeks) and after eating dinner with Kira and Cosima. Kira still seems unsure about the whole thing, though she's been polite enough in class and on the handful of "family dinners" Cosima has insisted they attempt to have. She has grown into a young woman who looks very much like Sarah—specifically Sarah, too, which should be impossible and has happened anyway. Delphine rather likes her.

She isn't thinking about Kira, though, as Cosima's mouth moves across her throat and bites at tendon and pulse. The walk back to her apartment had been quiet, Cosima's hand familiar and welcome in her own, her kiss when they stepped inside soft. Now, crashed on the sofa with Cosima in her lap, Delphine feels anything but gentle.

"What was the thing, earlier?" It takes her a moment to understand the words, kissed into the join of her neck and shoulder.

"The thing—oh.  _Oh_. I was thinking about your hands."

Cosima leans back enough to raise her eyebrows, starting to smile apparently despite herself. "That could really mean anything. Specificity is a virtue, Dr Cormier."

She'd like to protest that it is  _not_  a virtue, but Cosima is busy tangling one of her hands in Delphine's hair and it makes her mind go briefly blank. After a pause, she manages a weak shrug and weaker laugh. "I don't know what to say—'I was thinking about your hands' rather covers the whole thought."

The fingers in her hair twist and tug, not sharp but still a warning. Cosima runs her tongue along the edge of her teeth, eyebrows half raised, and it is everything Delphine has not to lean up and kiss her, hard, pull her hips down to grind against Delphine's own, but she has learnt  _some_  patience—and when Cosima should be obeyed. So, instead, she takes Cosima's free hand in both of her own, cradling it between their bodies. She carefully, gently straightens each finger, her touch light.

"I was thinking about your hands," she repeats, then ducks her head a little to run her tongue across the pad of Cosima's thumb. Rewarded by a low groan, Delphine smiles and does it again, then slides her mouth down and sucks briefly. Cosima's breath catches, high and sharp, and her hips jolt against Delphine's pelvis. Part of her is laughing, but most of her is concentrating on doing the same to each finger in turn. She bites at the heel of Cosima's palm, teeth finding and worrying soft skin, and then again at the bone of her wrist.

The hand in her hair tightens, tugging Delphine's head back. She looks up obligingly, and finds Cosima is no longer smiling, her eyes gone dark. "There are other things I could do with my hands, you know."

Delphine kisses her, because she must, because if she does not she will always regret it. "I think," she says into Cosima's mouth, "that you should show me—just in case I've forgotten anything I would rather remember when you're not here."

Six weeks was never going to be enough.

**Notes for the Chapter:**

> I know, I swore it was done, but thosefarplaces is extremely convincing.


End file.
